A wide variety of polymers have been used and suggested for use as membrane materials in membrane processes, such as for use in microfiltration, ultrafiltration, reverseosmosis and electrodialysis membrane processes. Polymer membranes are employed for selectively separating molecules, ions and suspended particles from carrier fluids. Polymer membranes have been employed and suggested for ultrafiltration purposes, for separating proteins and other comparatively large molecules from water, such as, for example, the separation of proteins from lactose and mineral salts in whey, which is a by-product of the dairy industry.
In separations involving water-based carriers, it is desirable to employ a membrane which has good mechanical strength and which also exhibits excellent chemical resistance to facilitate cleaning. This application is directed to a process for preparing improved membranes which overcome some of the problems and difficulties of preparing membranes in the prior art, and which improved membranes are useful for solid-liquid or solid-gas separation, especially in corrosive environments.